Weather in San Luis Potosí: Month-by-Month Guide + Best Time to Visit (2026)

By San Luis Way EditorialJuly 3, 2026

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San Luis Potosí's weather secret is altitude: at roughly 1,860 m, the capital gets 300+ days of high-desert sun, mild afternoons in every month and nights that always cool down. Here is the month-by-month climate table (SMN 1991–2020 normals), the best time to visit for each kind of trip — and the crucial catch: the Huasteca Potosina, three hours east, runs on a completely different climate.

Short answer: visit the city October–April (dry, clear, 21–30°C days); do the Huasteca waterfalls November–March (turquoise water, before the late-dry-season lows); expect the hottest sun in May, the heaviest rain in September, and near-freezing dawns December–February.

San Luis Potosí city, month by month

SMN/CONAGUA climate normals 1991–2020. City figures are shown as ranges across the two SLP city stations (24069 and 24111, ~1,870 m); rain days = days with measurable rain.

Month	High (°C)	Low (°C)	Rain (mm)	Rain days	In short
January	21–22	4–7	13–14	4–8	Coldest month — sunny afternoons, near-freezing dawns
February	23–25	5–8	11–12	3–5	Dry and warming; nights still cold
March	26–27	7–10	8–9	3–4	Driest stretch of the year; real spring warmth
April	29–30	10–13	11	3–4	Hot, dry and clear — Huasteca rivers at their lowest
May	29–31	12–14	37–44	7–9	Hottest, sunniest month; first storms at the end
June	27–29	13–15	59	9–11	Rainy season arrives — afternoon and evening storms
July	26–28	12–14	62–76	10	Warm days, regular evening rain, green hills
August	26–28	12–14	48–55	10	FENAPO month: warm, with evening showers
September	24–26	12–14	75–82	13	Wettest, cloudiest month of the year
October	24–25	9–12	31–33	8–11	Rains fade; the long clear season begins
November	22–24	6–9	12–15	4–8	Dry, mild days, chilly nights; turquoise water returns to the Huasteca
December	21–23	4–7	7–8	2–8	Driest month; crisp, bright winter days

Annual totals: 386–404 mm of rain over 81–95 rain days. Per WeatherSpark, the clearer part of the year starts around late October and lasts about 7.7 months, May is the sunniest month, September the most overcast — and muggy humidity is essentially zero year-round at this altitude.

The altitude effect: pack for two seasons every day

The city's semi-arid highland climate means a 15–17°C swing between afternoon and dawn is normal. A 22°C sunny January afternoon can follow a 4°C morning — and SMN station records show sub-zero minima in every month from October through March (down to −8°C in January and −8.5°C in December at station 24111). Whatever the month: sunscreen for midday, a real layer for after dark.

One state, two climates: the city vs the Huasteca

This is the mistake that ruins packing lists: checking the capital's forecast for a Huasteca trip. Ciudad Valles — the waterfall hub, 87 m above sea level — is hot, humid lowland. It gets three times the rain of the capital (1,208 mm vs ~400 mm a year), average May highs of 36°C with recorded extremes near 48°C, and summer nights that stay above 22°C. Meanwhile the capital never averages above 31°C in any month and always cools down at night.

Ciudad Valles (Huasteca), month by month

SMN/CONAGUA normals 1991–2020, station 24012 (87 m).

Month	High (°C)	Low (°C)	Rain (mm)
January	25.1	12.4	23.6
February	28.0	14.0	17.4
March	31.3	16.9	32.1
April	34.2	19.6	40.4
May	36.0	22.2	95.8
June	35.7	23.0	184.7
July	34.2	22.5	235.4
August	35.0	22.5	158.6
September	32.9	21.7	243.6
October	31.1	19.3	113.9
November	28.2	16.1	41.4
December	25.9	13.4	21.5

Practical translation: June–October the Huasteca rivers run high and brown with sediment; roughly November through April they turn the famous turquoise. Full logistics in our 3/5/7-day Huasteca itinerary.

Best time to visit, by type of trip

City sightseeing & food

Oct–Apr

The dry season is the city at its best: near-daily sun, 21–27°C afternoons for walking the centro histórico, and only 2–8 rain days a month. November–February needs layers for cold nights; March–April adds real warmth without the rains. May works too if you like it hot (29–31°C) — it is the sunniest month, with storms only arriving at the very end. Ideas for the visit: our visitor guide and the 7 verified day trips.

Huasteca waterfalls

Nov–Mar

November to March is the sweet spot: turquoise water, rafting season on the Tampaón, bearable lowland heat. Two honest caveats. First, June–October the rivers run high and sediment-brown — spectacular volume, no postcard color, and some activities pause. Second, the late dry season is now a real risk: Tamul waterfall was reported nearly dry in early 2024 and again in April–May 2026 (upstream irrigation extraction plus heat, per La Jornada), so April–May visitors should temper waterfall expectations. Plan it properly with the Huasteca itinerary.

FENAPO (the state fair)

August

FENAPO 2026 runs August 7–30. August is mid-rainy-season but kind: 26–28°C days, 12–14°C nights and ~10 rain days in the month, usually short evening showers rather than washouts. Fair strategy: light rain layer for the evening, something warm for the post-palenque walk to the car — at 1,860 m the night air bites even in summer. Lineup, tickets and logistics: our FENAPO 2026 hub.

Xantolo (Day of the Dead in the Huasteca)

Late Oct–early Nov

Xantolo weather is transition weather: in Ciudad Valles, October still averages 31°C highs with 114 mm of rain, while November drops to 28°C and 41 mm — so the celebration usually lands right as the rains switch off and before the turquoise water fully returns. Warm days, mild nights (16–19°C), and a real chance of a shower in the last October days. If you base in the capital those same nights run 6–12°C — pack for both.

FAQ

What is the best time to visit San Luis Potosí?+

For the city, October to April: the dry, clear season, with mild sunny days (21–30°C highs) and almost no rain. For turquoise water in the Huasteca Potosina, November to March is the sweet spot — rivers have cleared after the rains but have not yet hit the late-dry-season lows that have left Tamul waterfall nearly dry in April–May (documented in 2024 and again in 2026). For FENAPO, the state fair (August 7–30, 2026), come in August and expect warm days with evening showers.

When is the rainy season in San Luis Potosí?+

In the city, roughly late May through early October, with June–September concentrating most of the ~386–404 mm annual total and September the wettest month (75–82 mm). The Huasteca lowland gets about three times more rain: Ciudad Valles records 1,208 mm a year, with 235 mm in July and 244 mm in September alone (SMN climate normals 1991–2020).

How cold does San Luis Potosí get in winter?+

The city sits at roughly 1,860 m, so winter is about cold nights, not cold days: December–January afternoons still reach 21–23°C, but overnight lows average 4–7°C, and SMN station records show sub-zero minima in every month from October through March. Pack real layers for mornings and evenings.

Is the weather in the Huasteca Potosina the same as in the city?+

No — they are two different climates in one state. The capital is semi-arid highland at ~1,860 m: ~400 mm of rain a year, dry air and cool nights year-round. Ciudad Valles, the Huasteca hub, sits at 87 m: hot and humid, 36°C average May highs, 1,208 mm of annual rain, and nights that rarely cool below 22°C in summer. Check both forecasts if your trip covers both.

What is the weather like during FENAPO in August?+

Warm and manageable: August in the city averages 26–28°C highs and 12–14°C lows, with around 10 rain days in the month (48–55 mm total) — typically brief evening showers. Bring a light rain layer and something warm for late-night palenque exits; at this altitude the temperature drops fast after sunset.

Sources

Temperature, rainfall and rain-day figures: SMN/CONAGUA climate normals 1991–2020 for stations 24069 San Luis Potosí (DGE), 24111 San Luis Potosí (SMN) and 24012 Ciudad Valles, retrieved July 2026; city values are shown as ranges across the two urban stations. Sunshine/cloud-cover seasonality: WeatherSpark (modeled data). Turquoise-water vs sediment season: Huasteca-Potosina.com and regional guides. Tamul low-water episodes: La Jornada (Feb 2024 and May 6, 2026) and Potosinoticias (Apr 27, 2026). Climate classification and altitude: Wikipedia (BSh semi-arid; 1,864 m) and SMN station metadata (1,870–1,903 m). Normals are 30-year averages — any given year can vary.

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